• The Korean Journal of Ecology
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• v.26 no.3
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• pp.129-134
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• 2003

Amounts of CO₂ fixed by net primary production and released by soil respiration were determined on big-cone pine plantation. Net primary production, which was determined by allometric method, was converted into CO₂. CO₂ evolution in forest ecosystems are mainly through soil and root respiration. In order to separate root respiration from soil respiration, root-free sites were made in stand. Litter removal sites were prepared to estimate CO₂ evolution through litter layer. Respiration was measured at every two weeks intervals from April 2001 through April 2002, and soil temperature and soil moisture were measured at the same time. Net primary production of this big-cone pine plantation was 25.7 t·ha/sup -1/·yr/sup -1/. The amount of CO₂ fixed by this plantation was 42.5 t CO₂·ha/sup -1/·yr/sup -1/, The amount of CO₂ released by soil respiration was 5.0 t CO₂·ha/sup -1/·yr/sup -1/. The relative contribution of root respiration and litter layer respiration to total respiration was 46% and 32%, respectively. Net amount of fixed CO₂ was 37.5 t CO₂·ha/sup -1/·yr/sup -1/ in this big-cone pine plantation. From this result, this big-cone pine plantation play a carbon sink source from the atmosphere.

• Microbiology and Biotechnology Letters
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• v.25 no.1
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• pp.106-108
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• 1997

Blue green algaes (NIES 19, 39, 46) have been cultivated to product sigle cell protein. After 7 days of cultivation under 5000 (W/M$^{2}$) of ligth intensity, final cell concentration was 2.8 (g/L) and chlorophyll a was 4.9 (mg/L). When initial concentration of NaHCOC was 1.7% and NaNO$_{3}$ was0.25%, maximum cell concentration was obtained. Spirulina platensis NIES 39 showed faster growth rate than NIES 46. While most 39 sedimented, most 46 floated.

• Microbiology and Biotechnology Letters
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• v.25 no.3
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• pp.235-239
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• 1997

Chlorococcum littorale has been grown in high $CO_2$ concentrations to utilize $CO_2$ gas in the polluted air. The effect of incident light intensity on the specific growth rate is expressed by a photoinhibition model, showing half- saturation constant, $K_0\;as\;8\;(W/m^2)$ and inhibition constant, Ki as 35 $(W/m^2)$. The maximum specific growth rate was also estimated as 0.095 (1/day) under this condition. This strain maintained the optimum growth rate in 20% of $CO_2$ gas but 50% of input $CO_2$ gas is the maximum concentration considering the economical efficiency. The maximum Specific $CO_2$ consumption rate, $qCO_2$ was measured as 17.48 (mg $CO_2/g$ dry wt./day) in batch cultivation, 11.2 (mg $CO_2/g$ dry wt./day) in fed-batch cultivation and 10.87 (mg $CO_2/g$ dry wt./day) at 0.065 (1/day) of dilution rate in continuous cultivation. The chemical composition of the biomass obtained from this process showed 32.5% of protein, 27.5% of lipid, 16.5% of carbohydrate and ash 11.7%.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2004.11a
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• pp.93-94
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• 2004

• Mineral and Industry
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• v.22 no.1
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• pp.71-85
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• 2009

• Journal of the Korean Applied Science and Technology
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• v.32 no.1
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• pp.116-126
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• 2015

The present study utilized a shuttle mechanism of wet chemical absorption using MEA. In addition, industrial by-products containing a large amount of inorganic alkali substances were utilized for wet carbonization process. Chemical pretreatment of industrial by-products extracted calcium ions. ICP result of calcium ion was obtained up to 17,900 ppm(17.9%) by acidic substance. And also, In this work, 94% of recovery rate was obtained using wet MEA absorption process from $CO_2$ flow at the ambient condition. Through the liquid carbonation process, a sludge was fixed with rate of 0.175 mg of $CO_2$ per mg of sludge. It was found from XRD results that the structure of final product was composed of a calcite structure which is general structure of $CaCO_3$.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2003.11a
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• pp.485-486
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• 2003

산업사회의 발전과 문화생활의 향상에 따라 에너지 사용은 계속 증가해 왔으며, 이에 따른 환경문제 또한 꾸준히 제기되고 있다 산업구조상 화석연료를 주 에너지원으로 사용하고 있는 우리나라의 경우 온실 가스중 $CO_2$가 87.7%를 차지한다. 또한 이 $CO_2$가 대기 중에서 10.0%가 초과되면 인체에 심각한 신진대사의 이상, 중앙신경계의 장애가 발생할 수 도 있다(환경부, 2000). 에너지 경제연구원은 "2010년까지 2000년 수준으로 $CO_2$ 배출량을 줄이면서 국내 총생산은 17.5% 감소할 전망"이라고 분석했다(에너지 관리공단, 2003). (중략)

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.05a
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• pp.82-87
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• 1995

Carbon dioxide fixation by microalgae has several advantages such as no requirements for the pretreatment over phycal and/or chemical $CO_2$ fixation processes. Chlorella sp. HA-1, fresh algae. and Chlorococcum littorale. marine algae, were used to do $CO_2$ fixation work. The experimental parameters were light intensity and $CO_2$ concentration. Chlorella sp. HA-1 has the maximum growth rate at 8 Klux and 10% $CO_2$ concentration. Chlorococcum littorale showed the maximum growth at similar conditions. The results indicated the feasibility of the Chlorella HA-1 and Chlorococcum littorale for mass cultivation using flue gas.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2003.05a
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• pp.679-684
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• 2003

급속한 경제성장과 산업발달로 인해 국내외 에너지 소비량은 매년 크게 증가하고 있으며 이에 따라 화석연료의 사용도 증가하는 추세이다. 연소반응을 통한 화석연료의 사용은 GHG 중 가장 큰 요인인 $CO_2$를 배출한다. 따라서 막대한 양으로 배출되고 있는 $CO_2$ 발생을 억제하기 위하여 다양한 이산화탄소 고정화 기술이 연구 중에 있다. 그 중에서 경제성이 있고, 환경친화적이며 대량의 $CO_2$를 안정적이고 영구적으로 처리할 수 있는 기술로 주목되고 있는 연구가 광물질을 이용한 $CO_2$ 미네랄 Carbonation 처리기술에 대하여 반응특성을 고찰하였다. 대상 광물질로 Ca 보다 $CO_2$ 처리 시 친화적인 것으로 알려진 Mg가 많이 함유된 Silicate 계열의 사문석(Serpentine[Mg$_3$Si$_2$O$_{5}$(OH)$_4$])을 대상으로 Carbonation 반응특성을 실험을 통하여 고찰하였다. 실험은 TGA를 이용한 분석실험과 200cc 급 Autoclave를 이용한 $CO_2$의 직접주입실험을 수행하였다. TGA분석과 200cc 급 Autoclave를 이용한 실험을 통해서 Serpentine 의 경우 실험에서 정한 운전조건에서 $CO_2$와의 Carbonation 반응에 적합한 물질로 판단된다는 결론을 도출하였다.

• Journal of the Korean Magnetics Society
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• v.16 no.3
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• pp.173-177
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• 2006

We have investigated the magnetoresistance (MR) effect of the spin valve structures composed of perpendicularly magnetized Pd/Co multilayers, with changing the space layer (Pd or Cu) thickness, the stacking number of the Pd/Co multilayers, and the Co insertion-layer thickness. The Cu space layer showed larger MR ratio than the Pd space layer. The Co insertion-layer between Cu layer and pinned layer enhanced the MR ratio about three times. The maximum MR ratio of 7.4 % was established in the sample with the Co insertion-layer thickness of 0.62 and 1.01 nm.